ATL: LISA - Advisories

[cycloneye]

000
WTNT24 KNHC 210231
TCMAT4
TROPICAL DEPRESSION FOURTEEN FORECAST/ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
0300 UTC TUE SEP 21 2010

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

TROPICAL DEPRESSION CENTER LOCATED NEAR 17.1N 31.9W AT 21/0300Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE NORTH OR 360 DEGREES AT 5 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1006 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 17.1N 31.9W AT 21/0300Z
AT 21/0000Z CENTER WAS LOCATED NEAR 17.0N 31.9W

FORECAST VALID 21/1200Z 17.5N 31.7W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 35NE 30SE 0SW 20NW.

FORECAST VALID 22/0000Z 18.0N 31.6W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 50NE 40SE 25SW 40NW.

FORECAST VALID 22/1200Z 18.4N 31.8W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 50NE 40SE 30SW 40NW.

FORECAST VALID 23/0000Z 18.9N 32.4W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 60NE 45SE 35SW 50NW.

FORECAST VALID 24/0000Z 20.1N 34.4W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 30NE 25SE 0SW 25NW.
34 KT... 70NE 60SE 50SW 65NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 200 NM
ON DAY 4 AND 250 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 25/0000Z 22.0N 35.5W
MAX WIND 55 KT...GUSTS 65 KT.

OUTLOOK VALID 26/0000Z 23.5N 35.5W
MAX WIND 55 KT...GUSTS 65 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.1N 31.9W

NEXT ADVISORY AT 21/0900Z

$$
FORECASTER CANGIALOSI

000
WTNT34 KNHC 210232
TCPAT4
BULLETIN
TROPICAL DEPRESSION FOURTEEN ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM EDT MON SEP 20 2010

...TROPICAL DEPRESSION FOURTEEN FORMS OVER THE TROPICAL EASTERN
ATLANTIC...

SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...17.1N 31.9W
ABOUT 530 MI...850 KM W OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/HR
PRESENT MOVEMENT...N OR 360 DEGREES AT 6 MPH...9 KM/HR
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM EDT...0300 UTC...THE CENTER OF TROPICAL DEPRESSION
FOURTEEN WAS LOCATED NEAR LATITUDE 17.1 NORTH...LONGITUDE 31.9 WEST.
THE DEPRESSION IS MOVING TOWARD THE NORTH NEAR 6 MPH...9 KM/HR...AND
THIS GENERAL MOTION IS FORECAST DURING THE NEXT DAY OR SO. A TURN
TO THE NORTHWEST WITH A SLIGHT INCREASE IN FORWARD SPEED IS FORECAST
ON WEDNESDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND THE DEPRESSION IS FORECAST TO BECOME A TROPICAL STORM ON
TUESDAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 AM EDT.

$$
FORECASTER CANGIALOSI

000
WTNT44 KNHC 210233
TCDAT4
TROPICAL DEPRESSION FOURTEEN DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM EDT MON SEP 20 2010

SATELLITE IMAGES INDICATE THAT THE AREA OF LOW PRESSURE LOCATED
ABOUT 450 N MI WEST OF THE CAPE VERDE ISLANDS HAS DEVELOPED
ENOUGH ORGANIZED CONVECTION TO BE CLASSIFIED A TROPICAL
DEPRESSION...THE FOURTEENTH OF THE 2010 ATLANTIC HURRICANE SEASON.
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB ARE 35 KT AND 30
KT...RESPECTIVELY. BASED ON THESE ESTIMATES...THE INITIAL INTENSITY
IS SET AT 30 KT. DEEP CONVECTION HAS BEEN INCREASING IN INTENSITY
AND COVERAGE DURING THE PAST COUPLE OF HOURS AND THE DEPRESSION
IS NEARING TROPICAL STORM STRENGTH.

THE INITIAL MOTION ESTIMATE IS 360/5...BASED MAINLY ON SATELLITE
FIXES. THE DEPRESSION IS CAUGHT IN WEAK STEERING CURRENTS TO THE
SOUTH OF A LARGE DEEP-LAYER TROUGH OVER THE EASTERN ATLANTIC OCEAN.
A GENERAL SLOW NORTHWARD MOTION IS EXPECTED FOR THE NEXT 24 TO 36
HOURS AS THE SYSTEM REMAINS IN THE WEAK FLOW. A TURN TO THE
NORTHWEST IS PROBABLE IN A COUPLE OF DAYS AS THE TROUGH SHIFTS EAST
AND FLATTENS...ALLOWING FOR SOME MID-LEVEL RIDGING TO BUILD NORTH
OF THE CYCLONE. ANOTHER TROUGH...HOWEVER...IS EXPECTED TO PASS
NORTH OF THE SYSTEM BY THE END OF THE FORECAST PERIOD AND WILL
LIKELY INDUCE A SLOW NORTHWARD MOTION BY THAT TIME. THERE IS A
LARGE SPREAD IN THE MODEL GUIDANCE AND THE OFFICIAL TRACK FORECAST
IS OF LOWER CONFIDENCE THAN NORMAL.

MOST OF THE INTENSITY MODELS SHOW SOME STRENGTHENING DURING THE NEXT
FEW DAYS AS THE CYCLONE IS EXPECTED TO REMAIN OVER MARGINALLY WARM
SEA SURFACE TEMPERATURES AND IN A LOW WIND SHEAR ENVIRONMENT...BUT
JUST SOUTH OF STRONG WESTERLY UPPER-LEVEL WINDS. WESTERLY SHEAR
OVER THE SYSTEM COULD INCREASE IN 4 OR 5 DAYS...ASSOCIATED WITH THE
AFOREMENTIONED SECOND TROUGH. THE OFFICIAL FORECAST IS IN BEST
AGREEMENT WITH THE INTENSITY MODEL CONSENSUS AND SHOWS GRADUAL
STRENGTHENING FOR THE NEXT FEW DAYS FOLLOWED BY LITTLE CHANGE IN
STRENGTH THEREAFTER.

FORECAST POSITIONS AND MAX WINDS

INITIAL 21/0300Z 17.1N 31.9W 30 KT
12HR VT 21/1200Z 17.5N 31.7W 35 KT
24HR VT 22/0000Z 18.0N 31.6W 40 KT
36HR VT 22/1200Z 18.4N 31.8W 40 KT
48HR VT 23/0000Z 18.9N 32.4W 45 KT
72HR VT 24/0000Z 20.1N 34.4W 50 KT
96HR VT 25/0000Z 22.0N 35.5W 55 KT
120HR VT 26/0000Z 23.5N 35.5W 55 KT

$$
FORECASTER CANGIALOSI

[AJC3]

WTNT34 KNHC 210852
TCPAT4
BULLETIN
TROPICAL STORM LISA ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 AM EDT TUE SEP 21 2010

...DEPRESSION BECOMES TROPICAL STORM LISA...TWELFTH OF THE ATLANTIC
SEASON...


SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...17.7N 31.8W
ABOUT 530 MI...850 KM WNW OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/HR
PRESENT MOVEMENT...N OR 360 DEGREES AT 5 MPH...7 KM/HR
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 AM EDT...0900 UTC...THE CENTER OF TROPICAL STORM LISA WAS
LOCATED NEAR LATITUDE 17.7 NORTH...LONGITUDE 31.8 WEST. LISA IS
MOVING TOWARD THE NORTH NEAR 5 MPH...7 KM/HR...AND THIS GENERAL
MOTION IS EXPECTED TO CONTINUE DURING THE NEXT 24 HOURS. A TURN
TOWARD THE NORTH-NORTHWEST WITH A SLIGHT DECREASE IN FORWARD SPEED
IS FORECAST ON WEDNESDAY...FOLLOWED BY A TURN TOWARD THE
WEST-NORTHWEST ON THURSDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. SOME ADDITIONAL STRENGTHENING IS FORECAST DURING THE NEXT
COUPLE OF DAYS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 40 MILES...65 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM EDT.

$$
FORECASTER ROBERTS/BEVEN



WTNT24 KNHC 210849
TCMAT4
TROPICAL STORM LISA FORECAST/ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
0900 UTC TUE SEP 21 2010

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

TROPICAL STORM CENTER LOCATED NEAR 17.7N 31.8W AT 21/0900Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE NORTH OR 360 DEGREES AT 4 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 35NE 35SE 0SW 20NW.
12 FT SEAS.. 30NE 30SE 0SW 0NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 17.7N 31.8W AT 21/0900Z
AT 21/0600Z CENTER WAS LOCATED NEAR 17.5N 31.8W

FORECAST VALID 21/1800Z 18.0N 31.7W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 60NE 45SE 35SW 50NW.

FORECAST VALID 22/0600Z 18.4N 31.7W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 20NE 0SE 0SW 20NW.
34 KT... 70NE 60SE 50SW 65NW.

FORECAST VALID 22/1800Z 18.7N 31.9W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 25NE 20SE 15SW 25NW.
34 KT... 80NE 70SE 60SW 80NW.

FORECAST VALID 23/0600Z 19.0N 32.6W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 25NE 20SE 15SW 25NW.
34 KT... 80NE 70SE 60SW 80NW.

FORECAST VALID 24/0600Z 19.8N 34.3W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 25NE 20SE 15SW 25NW.
34 KT... 80NE 70SE 60SW 80NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 200 NM
ON DAY 4 AND 250 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 25/0600Z 20.5N 35.5W
MAX WIND 50 KT...GUSTS 60 KT.

OUTLOOK VALID 26/0600Z 21.5N 37.0W
MAX WIND 45 KT...GUSTS 55 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.7N 31.8W

NEXT ADVISORY AT 21/1500Z

$$
FORECASTER ROBERTS/BEVEN

WTNT44 KNHC 210855
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 AM EDT TUE SEP 21 2010

ENHANCED INFRARED AND SHORTWAVE IMAGERY...ALONG WITH AN AMSU
OVERPASS..INDICATE THAT THE TROPICAL CYCLONE HAS BECOME BETTER
ORGANIZED. BURSTS OF DEEP CONVECTION ARE FORMING NEAR THE
CIRCULATION CENTER...AND CLOUD TOPS ASSOCIATED WITH A BANDING
FEATURE OVER THE EAST SEMICIRCLE HAVE COOLED TO -70 CELSIUS.
DVORAK SATELLITE INTENSITY ESTIMATES ARE T2.5...35 KT...FROM BOTH
TAFB AND SAB. THESE ESTIMATES ALONG WITH AN ADT ESTIMATE OF 39 KT
SUPPORT AN UPGRADE OF THE DEPRESSION TO A 35 KT TROPICAL STORM.

THE SHEAR IS LOW...AND ENVIRONMENTAL CONDITIONS ARE EXPECTED TO
REMAIN CONDUCIVE FOR FURTHER STRENGTHENING DURING THE NEXT 36
HOURS. THROUGH THE REMAINING PERIOD...THE LARGE-SCALE MODELS SHOW
AN UPPER ANTICYCLONE LOCATED OVER THE CENTRAL ATLANTIC OCEAN
RETROGRADING SOUTHWESTWARD TOWARD THE GREATER ANTILLES...AND A MID-
TO UPPER-LEVEL TROUGH TO THE NORTH OF LISA FILLING AND MOVING
NORTHEASTWARD. THIS CHANGE IN THE SYNOPTIC PATTERN IS EXPECTED TO
INCREASE THE WESTERLY SHEAR ALONG THE FORECAST TRACK. THE
INTENSITY FORECAST IS BASED ON THE AFOREMENTIONED SCENARIO AND IS A
COMPROMISE OF THE SHIPS MODEL AND THE LGEM.

THE INITIAL MOTION ESTIMATE IS 360/4...WITHIN THE WEAK STEERING
CURRENT ASSOCIATED WITH A BREAK IN THE SUBTROPICAL RIDGE OVER THE
EASTERN ATLANTIC. THE GLOBAL MODELS...AS WELL AS THE ECMWF AND GFS
ENSEMBLES...SUGGEST A RATHER SLOW NORTHWARD MOTION DURING THE NEXT
36 HOURS. BY DAY 2...A GRADUAL TURN TOWARD THE WEST-NORTHWEST IS
INDICATED AS THE TROUGH LIFTS NORTHEASTWARD AND THE SUBTROPICAL
RIDGE BUILDS IN TO THE NORTH OF THE CYCLONE. THE NHC OFFICIAL
TRACK FORECAST REFLECTS A BLEND OF THE GLOBAL AND ENSEMBLE
MODELS...AND IS SHIFTED TO THE LEFT OF THE PREVIOUS ADVISORY.


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/0900Z 17.7N 31.8W 35 KT
12HR VT 21/1800Z 18.0N 31.7W 45 KT
24HR VT 22/0600Z 18.4N 31.7W 50 KT
36HR VT 22/1800Z 18.7N 31.9W 55 KT
48HR VT 23/0600Z 19.0N 32.6W 55 KT
72HR VT 24/0600Z 19.8N 34.3W 55 KT
96HR VT 25/0600Z 20.5N 35.5W 50 KT
120HR VT 26/0600Z 21.5N 37.0W 45 KT

$$
FORECASTER ROBERTS/BEVEN

[cycloneye]

000
WTNT44 KNHC 211445
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 AM EDT TUE SEP 21 2010

INTERMITTENT BURSTS OF DEEP CONVECTION HAVE BEEN OCCURRING NEAR THE
WELL-DEFINED CIRCULATION CENTER NOTED IN A 21/0932Z SSMIS OVERPASS.
UPPER-LEVEL OUTFLOW HAS ALSO GRADUALLY BEEN IMPROVING TO THE NORTH
AND SOUTH OF LISA. THE INITIAL INTENSITY HAS BEEN INCREASED TO 40
KT BASED ON A BLEND OF DVORAK SATELLITE INTENSITY ESTIMATES OF
T2.5/35 KT FROM BOTH TAFB AND SAB...AND UW-CIMSS ADT CURRENT
INTENSITY ESTIMATES OF T3.5/45 KT.

AFTER A BRIEF JOG TO THE NORTHEAST A FEW HOURS AGO...LISA HAS
RESUMED A MOTION ESTIMATE OF 360/4. LISA IS EXPECTED TO MOVE SLOWLY
NORTHWARD FOR THE NEXT 24 HOURS OR SO DUE TO THE COMBINATION OF
WEAK STEERING CURRENTS ASSOCIATED WITH A BREAK IN THE SUBTROPICAL
RIDGE AND MODERATE NORTHWESTERLY FLOW ON THE WEST SIDE OF A
DEEP-LAYER TROUGH SITUATED TO THE NORTH OF THE CYCLONE. AS THE
AFOREMENTIONED TROUGH LIFTS OUT TO THE NORTHEAST BY 36-48 HOURS...
THE RIDGE TO THE NORTH OF LISA IS EXPECTED TO BUILD BACK IN AND
FORCE THE CYCLONE ON A SLOW WEST-NORTHWESTWARD TRACK. THE MODEL
GUIDANCE IS WIDELY DIVERGENT WITH THE HWRF/GFDL MODELS TAKING LISA
DUE NORTH THROUGHOUT THE FORECAST PERIOD...WHILE THE NOGAPS/GFDN
MODELS MOVE LISA DUE WEST. THE REST OF THE NHC MODEL GUIDANCE IS
SPREAD OUT EVENLY BETWEEN THESE TWO EXTREMES. SUCH A LARGE SPREAD
IN THE MODEL GUIDANCE TYPICALLY SUGGESTS THAT THE FORWARD MOTION
WILL BE RELATIVELY SLOW...AND THAT IS REFLECTED IN THIS FORECAST
PACKAGE. THE OFFICIAL FORECAST TRACK IS SIMILAR THE PREVIOUS
ADVISORY TRACK AND LIES A LITTLE NORTH OF THE MODEL CONSENSUS.

ALTHOUGH THE VERTICAL SHEAR IS EXPECTED TO REMAIN LOW FOR ABOUT THE
NEXT 72 HOURS...THE MID-LEVEL MOISTURE ENVIRONMENT SURROUNDING LISA
IS FORECAST TO DRY OUT CONSIDERABLY AND SSTS ARE EXPECTED TO DROP
BELOW 27C. THE DRIER AIR AND COOLER WATER MAY PUT THE BREAKS ON THE
INTENSIFICATION PROCESS AS THE CYCLONE NEARS HURRICANE STRENGTH IN
48-72 HOURS. AFTER 72 HOURS...LISA IS EXPECTED TO BEGIN FEELING THE
EFFECTS OF INCREASING WESTERLY SHEAR AS ANOTHER UPPER-LEVEL TROUGH
DIGS SOUTHWARD AND AMPLIFIES TO THE NORTHWEST OF THE CYCLONE. IT
SHOULD BE NOTED THAT THE ECMWF MODEL DOES NOT MOVE LISA NORTH OF
20N LATITUDE...WHICH KEEPS THE CYCLONE IN A LOWER SHEAR ENVIRONMENT
BENEATH AN UPPER-LEVEL ANTICYCLONE FROM 72-120 HOURS. THE OFFICIAL
INTENSITY FORECAST IS A BLEND OF THE SHIPS AND LGEM INTENSITY
MODELS...AND LEANS A LITTLE TOWARD THE STRONGER ECMWF SOLUTION.


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/1500Z 18.1N 31.7W 40 KT
12HR VT 22/0000Z 18.3N 31.7W 45 KT
24HR VT 22/1200Z 18.7N 31.8W 50 KT
36HR VT 23/0000Z 19.0N 32.2W 55 KT
48HR VT 23/1200Z 19.4N 33.0W 60 KT
72HR VT 24/1200Z 20.1N 34.5W 55 KT
96HR VT 25/1200Z 20.9N 35.8W 50 KT
120HR VT 26/1200Z 21.0N 37.5W 45 KT

$$
FORECASTER STEWART

[cycloneye]

HC 212034
TCDAT4

TROPICAL STORM LISA DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 PM EDT TUE SEP 21 2010

AFTER A SHORT-LIVED DECREASE IN THE CENTRAL CONVECTION...A BURST
OF STRONG CONVECTION HAS RECENTLY DEVELOPED OVER THE WELL-DEFINED
LOW-LEVEL CIRCULATION CENTER. RECENT TRMM AND AMSU MICROWAVE
OVERPASSES INDICATE THE LOW- AND MID-LEVEL CIRCULATIONS HAVE
TIGHTENED UP AND BECOME MORE VERTICALLY ALIGNED...SUGGESTING THAT
THE VERTICAL SHEAR AFFECTING THE SYSTEM HAS DECREASED. UPPER-LEVEL
OUTFLOW CONTINUES TO IMPROVE IN ALL QUADRANTS. THE INITIAL
INTENSITY REMAINS AT 40 KT BASED ON A BLEND OF DVORAK SATELLITE
INTENSITY ESTIMATES OF T2.5/35 KT FROM BOTH TAFB AND SAB...AND
UW-CIMSS ADT CURRENT INTENSITY ESTIMATE OF T3.4/53 KT.

THE INITIAL MOTION ESTIMATE IS 360/2. LISA HAS BEEN WOBBLING BETWEEN
A NORTH AND NORTHEAST DIRECTION...PROBABLY DUE TO RE-ORGANIZATION
OF THE SYSTEM CENTER. NOW THAT THE VERTICAL CIRCULATIONS APPEAR TO
BE MORE VERTICALLY ALIGNED...HOPEFULLY THIS WILL RESULT IN LESS
SCATTER IN THE SATELLITE FIX POSITIONS. LISA IS EXPECTED REMAIN IN
VERY WEAK STEERING FLOW FOR THE NEXT 48-72 HOURS. AFTERWARDS...A
MID-LEVEL TROUGH SITUATED JUST NORTH OF THE CYCLONE IS FORECAST TO
SLOWLY LIFT OUT TO THE NORTHEAST...ALLOWING THE SUBTROPICAL RIDGE
TO BUILD WESTWARD TO THE NORTH OF LISA...WHICH SHOULD NUDGE THE
CYCLONE ON A SLOW WESTWARD OR WEST-NORTHWESTWARD TRACK. THE NHC
MODEL GUIDANCE REMAINS WIDELY DIVERGENT BETWEEN THE NORTHWARD HWRF
AND THE WESTWARD GFDN MODEL SOLUTIONS. THE OFFICIAL FORECAST TRACK
IS SIMILAR THE PREVIOUS ADVISORY...AND REMAINS NORTH OF THE MODEL
CONSENSUS AND BETWEEN THE GFS AND ECMWF TRACKS.

THE VERTICAL SHEAR IS FORECAST TO REMAIN BELOW 10 KT FOR THE NEXT
48 HOURS...WHICH USUALLY FAVORS SIGNIFICANT INTENSIFICATION.
HOWEVER...MID-LEVEL MOISTURE IS FORECAST TO DECREASE WITH HUMIDITY
LEVELS BELOW 40 PERCENT AFTER 24 HOURS. DESPITE THE PRESENCE OF DRY
AIR...JULIA IS FORECAST TO STRENGTHEN FAIRLY QUICKLY IN THE NEXT 24
HOURS DUE TO THE IMPROVED INNER-CORE STRUCTURE NOTED IN THE
AFOREMENTIONED MICROWAVE IMAGERY. GIVEN THAT A 75-PERCENT EYEWALL
FEATURE EXISTED 6 HRS AGO AND CLOUD TOPS HAVE RECENTLY COOLED TO
BELOW -80C NEAR THE CENTER...A PERIOD OF RAPID INTENSIFICATION CAN
NOT BE RULED OUT. THE ECMWF MODEL CONTINUES TO KEEP LISA SOUTH OF
20N LATITUDE AND BENEATH AN UPPER-LEVEL ANTICYCLONE. THE OFFICIAL
INTENSITY FORECAST IS ABOVE THE OBJECTIVE INTENSITY GUIDANCE THROUGH
48 HOURS AND CONTINUES TO LEAN TOWARD THE STRONGER ECMWF SOLUTION.


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/2100Z 18.3N 31.6W 40 KT
12HR VT 22/0600Z 18.6N 31.7W 50 KT
24HR VT 22/1800Z 19.0N 31.9W 60 KT
36HR VT 23/0600Z 19.3N 32.5W 65 KT
48HR VT 23/1800Z 19.7N 33.3W 65 KT
72HR VT 24/1800Z 20.4N 34.7W 55 KT
96HR VT 25/1800Z 21.0N 36.0W 45 KT
120HR VT 26/1800Z 21.0N 38.0W 40 KT

$$
FORECASTER STEWART

[cycloneye]

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM LISA DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM EDT TUE SEP 21 2010

CONVENTIONAL SATELLITE AND MICROWAVE IMAGES INDICATE THAT LISA HAS
GENERALLY CHANGED LITTLE IN STRUCTURE DURING THE PAST FEW
HOURS...ALTHOUGH CLOUD TOPS HAVE WARMED SOME. SATELLITE INTENSITY
ESTIMATES ARE 45 KT AND 35 KT FROM TAFB AND SAB...RESPECTIVELY...
AND THE THE INITIAL WIND SPEED IS HELD AT 40 KT FOR THIS ADVISORY.
LISA HAS AN OPPORTUNITY TO STRENGTHEN DURING THE NEXT COUPLE OF
DAYS AS IT REMAINS IN A RELATIVELY LOW WIND SHEAR ENVIRONMENT AND
OVER SEA SURFACE TEMPERATURES NEAR 27 C. WESTERLY SHEAR...
ASSOCIATED WITH A MID- TO UPPER-LEVEL TROUGH...IS EXPECTED TO
INCREASE SIGNIFICANTLY IN ABOUT 3 DAYS. THIS...COMBINED WITH DRY
AIR...SHOULD CAUSE STEADY WEAKENING BY THE END OF THE FORECAST
PERIOD. THE OFFICIAL FORECAST IS HIGHER THAN ALL OF THE GUIDANCE
FOR THE NEXT COUPLE DAYS...GIVEN THE APPARENTLY FAVORABLE
ENVIRONMENTAL CONDITIONS IN THE SHORT TERM...AND THEN FOLLOWS A
BLEND OF THE LGEM AND SHIPS MODELS.

LISA APPEARS TO HAVE JOGGED TO THE EAST OVER THE PAST FEW
HOURS...AND THE LATEST 12-HOUR INITIAL MOTION ESTIMATE IS 040/2.
THE STORM REMAINS IN WEAK STEERING CURRENTS NEAR THE BASE OF A
LARGE AND AMPLIFIED DEEP-LAYER TROUGH OVER THE EASTERN ATLANTIC. A
SLOW AND LIKELY ERRATIC NORTH TO NORTH-NORTHWESTWARD MOTION IS
EXPECTED DURING THE NEXT DAY OR SO AS THE UPPER TROUGH REMAINS IN
PLACE. BEYOND A COUPLE OF DAYS...A GRADUAL TURN TO THE
WEST-NORTHWEST IS FORECAST AS THE TROUGH CUTS OFF AND LOW- TO
MID-LEVEL RIDGING BUILDS TO THE NORTH OF LISA. THE TRACK MODEL
GUIDANCE REMAINS IN POOR AGREEMENT AND THIS FORECAST IS OF LOW
CONFIDENCE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 22/0300Z 18.2N 31.3W 40 KT
12HR VT 22/1200Z 18.3N 31.3W 50 KT
24HR VT 23/0000Z 18.5N 31.4W 55 KT
36HR VT 23/1200Z 18.7N 31.6W 60 KT
48HR VT 24/0000Z 19.1N 32.3W 65 KT
72HR VT 25/0000Z 19.7N 33.5W 55 KT
96HR VT 26/0000Z 20.5N 35.5W 45 KT
120HR VT 27/0000Z 21.0N 38.0W 35 KT

$$
FORECASTER CANGIALOSI

[cycloneye]

TROPICAL STORM LISA DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 AM EDT WED SEP 22 2010

INFRARED SATELLITE IMAGES INDICATE THAT THERE HAS BEEN LITTLE
SIGNIFICANT CHANGE ASSOCIATED WITH THE CLOUD PATTERN OF LISA. THE
CYCLONE CONSISTS OF A CENTRAL MASS OF PULSATING DEEP CONVECTION...
ALTHOUGH WITH FEWER BANDING FEATURES THAN YESTERDAY. SEVERAL RECENT
MICROWAVE OVERPASSES SUGGEST THAT THE LOW- AND MID-LEVEL CENTERS
ARE NOT CO-LOCATED...A SIGN THAT THE CYCLONE IS BEING IMPACTED BY
VERTICAL WIND SHEAR. DVORAK CI NUMBERS AT 0600 UTC ARE AT 2.5 AND
3.0 FROM SAB AND TAFB...RESPECTIVELY. A BLEND OF THESE ESTIMATES
IS THE BASIS FOR KEEPING THE INITIAL INTENSITY AT 40 KT FOR THIS
ADVISORY.

THE CENTER HAS BEEN DIFFICULT TO LOCATE BUT RECENT MICROWAVE AND
SATELLITE FIXES SUGGEST THAT IT BE A LITTLE FARTHER SOUTH THAN
PREVIOUSLY INDICATED. A SHORT-TERM INITIAL MOTION FROM THESE FIXES
YIELDS AN ESTIMATE OF 060/4. THE TRACK GUIDANCE CONTINUES TO BE
FAIRLY DIVERGENT BUT GENERALLY SHOWS LISA DRIFTING SOUTH OR EAST IN
A REGION OF WEAK STEERING DURING THE 48 HOURS. AFTER THAT...A TURN
TOWARD WEST-NORTHWEST IS EXPECTED WITH A FASTER FORWARD SPEED AS A
WEAK LOW- TO MID-LEVEL RIDGE BUILDS NORTH OF THE STORM. GIVEN THE
LARGE SPREAD IN THE GLOBAL MODELS...THE NEW NHC TRACK FORECAST
REMAINS OF LOW CONFIDENCE AND IS SLOWED FURTHER UNTIL A MORE
ESTABLISHED TREND IS EVIDENT IN THE GUIDANCE.

WATER VAPOR IMAGERY SHOWS A SHARP UPPER-LEVEL TROUGH NORTH OF LISA
THAT IS FORECAST TO LIFT OUT IN 24-48 HOURS. THIS FEATURE HAS BEEN
IMPARTING A NORTHWESTERLY SHEAR OVER THE STORM...BUT SHIPS MODEL
OUTPUT INDICATES THAT THIS SHEAR SHOULD NOT BE PARTICULARLY STRONG
DURING THIS TIME. AFTER ABOUT 60-72 HOURS...HOWEVER...GLOBAL
MODELS FORECAST A STRENGTHENING OF UPPER-LEVEL WESTERLY FLOW OVER
LISA...AND THE INTENSITY GUIDANCE SHOWS WEAKENING LATER IN THE
PERIOD. OF COURSE...THE INTENSITY GUIDANCE IS HIGHLY DEPENDENT ON
WHERE LISA IS LOCATED AT THAT TIME...AND THE GREATER THAN NORMAL
UNCERTAINTY REGARDING ITS FORECAST TRACK MAKES THE CURRENT
INTENSITY FORECAST DIFFICULT. THE NEW NHC INTENSITY FORECAST HAS
BEEN ADJUSTED A BIT DOWNWARD BEFORE 72 HOURS BUT REMAINS AT OR
ABOVE THE STATISTICAL-DYNAMICAL OUTPUT.


FORECAST POSITIONS AND MAX WINDS

INITIAL 22/0900Z 18.0N 30.5W 40 KT
12HR VT 22/1800Z 18.0N 30.5W 45 KT
24HR VT 23/0600Z 17.9N 30.5W 50 KT
36HR VT 23/1800Z 17.8N 30.5W 50 KT
48HR VT 24/0600Z 17.8N 30.7W 55 KT
72HR VT 25/0600Z 18.5N 32.5W 50 KT
96HR VT 26/0600Z 19.5N 35.0W 45 KT
120HR VT 27/0600Z 21.0N 38.0W 35 KT

$$
FORECASTER KIMBERLAIN

[HURAKAN]

TROPICAL STORM LISA DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 AM EDT WED SEP 22 2010

LISA IS PRODUCING A SMALL AREA OF DEEP CONVECTION NEAR THE SURFACE
CENTER...BUT MUCH OF THE LOW-LEVEL CIRCULATION IS EXPOSED AROUND
THE CONVECTIVE MASS. DVORAK CURRENT INTENSITY ESTIMATES ARE 3.0/45
KT AND 2.5/35 KT FROM TAFB AND SAB...SO THE INITIAL INTENSITY IS
BEING MAINTAINED AT 40 KT. A FEW MICROWAVE PASSES...PARTICULARLY A
0919 UTC SSMIS PASS...INDICATED THAT THE CENTER OF LISA HAS DRIFTED
SOUTHEASTWARD OVERNIGHT AND IS NOW LOCATED JUST A LITTLE FARTHER
SOUTH THAN PREVIOUSLY ESTIMATED. THE BEST ESTIMATE OF THE INITIAL
MOTION IS 125 DEGREES AT 3 KT. LISA IS EXPECTED TO MOVE VERY
LITTLE DURING THE NEXT 48 HOURS AS IT REMAINS TRAPPED IN A
MID-LEVEL COL REGION BETWEEN A RIDGE TO THE EAST OVER AFRICA...A
RIDGE TO THE WEST OVER THE CENTRAL ATLANTIC...AND A SHARP TROUGH TO
THE NORTH BETWEEN THE AZORES AND CANARY ISLANDS. AFTER 48
HOURS...THE TROUGH IS EXPECTED TO LIFT NORTHEASTWARD TOWARDS EUROPE
AND THE AFRICAN RIDGE WILL THEN BUILD WESTWARD...NUDGING LISA A
LITTLE FARTHER WEST OVER THE ATLANTIC. THE TRACK GUIDANCE IS IN
AGREEMENT ON THIS SCENARIO... AND THE NHC FORECAST IS VERY CLOSE TO
THE MODEL CONSENSUS TVCN AND THE PREVIOUS FORECAST.

THE STRONGEST UPPER-LEVEL WINDS ARE LOCATED JUST NORTH OF THE
CYCLONE. SINCE THE STORM IS LOCATED WITHIN THE COL...THE SHEAR
DIRECTLY OVER THE CENTER IS RATHER LOW AT THIS TIME. HOWEVER...
THERE IS A LOT OF MID-LEVEL DRY AIR AROUND LISA...AND THAT COULD BE
WHAT IS PREVENTING INTENSIFICATION. SOME STRENGTHENING IS STILL
POSSIBLE DURING THE NEXT 48 HOURS WHILE THE SHEAR REMAINS
RELATIVELY LOW...BUT INCREASING SHEAR AFTER THAT TIME SHOULD CAUSE
WEAKENING. THERE IS GREATER SPREAD IN THE INTENSITY GUIDANCE AFTER
48 HOURS. THE OFFICIAL INTENSITY FORECAST...WHICH HAS AGAIN BEEN
LOWERED A BIT FROM THE PREVIOUS FORECAST...IS CLOSE TO THE MODEL
CONSENSUS DURING THAT TIME.

FORECAST POSITIONS AND MAX WINDS

INITIAL 22/1500Z 17.1N 30.5W 40 KT
12HR VT 23/0000Z 17.1N 30.3W 40 KT
24HR VT 23/1200Z 17.0N 30.3W 45 KT
36HR VT 24/0000Z 17.0N 30.7W 45 KT
48HR VT 24/1200Z 17.3N 31.3W 50 KT
72HR VT 25/1200Z 18.5N 33.0W 50 KT
96HR VT 26/1200Z 20.0N 35.0W 45 KT
120HR VT 27/1200Z 21.5N 38.5W 35 KT

$$
FORECASTER BERG

[cycloneye]

000
WTNT44 KNHC 222032
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 PM AST WED SEP 22 2010

LISA HAS A ROBUST CIRCULATION...BUT ALL THE DEEP CONVECTION REMAINS
LIMITED TO NEAR THE CENTER. THE CONVECTIVE STRUCTURE HAS CHANGED
LITTLE OVER THE PAST FEW HOUR HOURS...SO THE INITIAL INTENSITY IS
KEPT AT 40 KT. ALTHOUGH VERTICAL SHEAR IS LIGHT...THE CYCLONE IS
SURROUNDED BY MID-LEVEL DRY AIR AND IS LOCATED OVER AN AREA WHERE
THE OCEAN HEAT CONTENT IS RATHER LOW. THEREFORE ONLY A LITTLE
STRENGTHENING IS INDICATED IN THE OFFICIAL FORECAST DURING THE NEXT
48 HOURS...WHEN CONDITIONS WILL BE MOST FAVORABLE. WEAKENING IS
EXPECTED FROM DAYS 3-5 AS 30-40 KT OF WEST-SOUTHWESTERLY SHEAR
DEVELOPS OVER THE CYCLONE. THE FORECAST INDICATES LISA BECOMING A
TROPICAL DEPRESSION BY DAY 5...BUT IT IS POSSIBLE THAT IT COULD
HAVE DEGENERATED TO A REMNANT LOW OR TROUGH BY THAT TIME.

LISA HAS BEEN MEANDERING ALL DAY...AND THE ESTIMATED INITIAL MOTION
IS 090/3 BASED ON A 12-18 HOUR AVERAGE. MODEL GUIDANCE SUGGESTS
THAT LISA COULD DRIFT A LITTLE FARTHER EASTWARD OR SOUTHEASTWARD
DURING THE NEXT 12-24 HOURS IN WEAK STEERING FLOW...BUT IT IS
EXPECTED TO PICK UP SOME SPEED AND MOVE NORTHWESTWARD BY 48 HOURS
AS A MID-LEVEL RIDGE OVER AFRICA BUILDS WESTWARD. THE TRACK
GUIDANCE HAS SHIFTED TO THE NORTH...AND THE OFFICIAL FORECAST IS
ABOUT 2 DEGREES FARTHER NORTH THAN THE PREVIOUS ONE BY DAY 5.

FORECAST POSITIONS AND MAX WINDS

INITIAL 22/2100Z 17.7N 30.2W 40 KT
12HR VT 23/0600Z 17.6N 29.9W 40 KT
24HR VT 23/1800Z 17.8N 29.9W 45 KT
36HR VT 24/0600Z 18.1N 30.6W 45 KT
48HR VT 24/1800Z 18.6N 31.2W 50 KT
72HR VT 25/1800Z 20.1N 32.7W 45 KT
96HR VT 26/1800Z 22.0N 35.0W 40 KT
120HR VT 27/1800Z 24.0N 38.0W 30 KT

$$
FORECASTER BERG

[Florida1118]

000
WTNT34 KNHC 230240
TCPAT4
BULLETIN
TROPICAL STORM LISA ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM AST WED SEP 22 2010

...LISA BARELY A TROPICAL STORM...MEANDERING OVER THE TROPICAL
EASTERN ATLANTIC...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...17.7N 29.6W
ABOUT 390 MI...625 KM WNW OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/HR
PRESENT MOVEMENT...E OR 90 DEGREES AT 5 MPH...7 KM/HR
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM AST...0300 UTC...THE CENTER OF TROPICAL STORM LISA WAS
LOCATED NEAR LATITUDE 17.7 NORTH...LONGITUDE 29.6 WEST. LISA IS
MOVING TOWARD THE EAST NEAR 5 MPH...7 KM/HR. A SLOW AND ERRATIC
MOTION IS LIKELY ON THURSDAY. A NORTHWEST MOTION WITH A GRADUAL
INCREASE IN FORWARD SPEED IS EXPECTED ON FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS POSSIBLE DURING THE NEXT 48 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 50 MILES...85 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 AM AST.

$$
FORECASTER CANGIALOSI

[cycloneye]

000
WTNT44 KNHC 230836
TCDAT4
TROPICAL DEPRESSION LISA DISCUSSION NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 AM AST THU SEP 23 2010

THE SATELLITE APPEARANCE OF LISA HAS CHANGED LITTLE DURING THE LAST
SEVERAL HOURS. BURSTS OF DEEP CONVECTION CONTINUE TO FORM PRIMARILY
NORTHEAST OF THE CIRCULATION CENTER BUT GENERALLY LACK MUCH
ORGANIZATION. THE CLOUD SHIELD ASSOCIATED WITH LISA HAS ALSO BECOME
MORE ASYMMETRIC DURING THE LAST 12 HOURS AND SEEMS PARTIALLY
INVOLVED WITH A SHARP MID- TO UPPER-LEVEL TROUGH LOCATED NORTHEAST
OF THE CYCLONE. DVORAK T-NUMBERS FROM SAB AND TAFB AT 0600 UTC HAVE
DECREASED TO 1.5 AND 2.5...RESPECTIVELY. BASED UPON THESE
ESTIMATES AND DATA FROM AN EARLIER ASCAT PASS...THE INITIAL
INTENSITY IS LOWERED TO 30 KT. AS LISA ESCAPES THE INFLUENCE OF THE
NEARBY MID-LATITUDE TROUGH DURING THE NEXT DAY OR TWO...THE
STATISTICAL-DYNAMICAL GUIDANCE STILL INDICATES THE POTENTIAL FOR
SOME MINOR RE-INTENSIFICATION. HOWEVER...WATERS ALONG THE FORECAST
TRACK ARE MARGINALLY WARM...THE OCEANIC HEAT CONTENT IS NOT
ESPECIALLY HIGH...AND THE CYCLONE SHOULD ENCOUNTER A SOMEWHAT
STABLE ENVIRONMENT. BEYOND 48 HOURS...WESTERLY SHEAR ASSOCIATED
WITH A NEW UPPER-LEVEL TROUGH DIGGING TO THE NORTHWEST OF LISA IS
EXPECTED TO INCREASE SIGNIFICANTLY AND RESULT IN WEAKENING WHICH
COULD OCCUR FASTER THAN CURRENTLY FORECAST. THE OFFICIAL NHC
INTENSITY FORECAST IS LOWERED TO ACCOUNT FOR CURRENT TRENDS AND IS
IN GOOD AGREEMENT WITH THE LATEST SHIPS/LGEM OUTPUT.

LISA HAS CONTINUED MOVING EASTWARD IN A WEAK WESTERLY STEERING
FLOW...AND THE INITIAL MOTION ESTIMATE IS 090/04. AS THE MID- TO
UPPER-LEVEL TROUGH IMPARTING THIS MOTION LIFTS OUT DURING THE NEXT
12-24 HOURS...GLOBAL MODELS SHOW A LOW- TO MID-LEVEL RIDGE BUILDING
NORTH OF LISA WHICH SHOULD LEAD TO A GRADUAL NORTHWESTWARD TURN
WITH AN INCREASE IN FORWARD SPEED. THE TRACK GUIDANCE HAS BEEN IN
REASONABLY GOOD AGREEMENT ON THIS SCENARIO...ALTHOUGH THE GFDL/
HWRF CONTINUE TO BE RIGHT OUTLIERS AS A RESULT OF WEAKER RIDGING.
THE NEW NHC TRACK FORECAST IS A BASICALLY AN UPDATE OF THE PREVIOUS
ONE AND IS LEFT OF THE MULTI-MODEL CONSENSUS...DOWNPLAYING THE
CONTRIBUTION OF THE GFDL/HWRF.


FORECAST POSITIONS AND MAX WINDS

INITIAL 23/0900Z 17.7N 29.0W 30 KT
12HR VT 23/1800Z 18.1N 29.0W 30 KT
24HR VT 24/0600Z 18.5N 29.6W 35 KT
36HR VT 24/1800Z 19.1N 30.3W 40 KT
48HR VT 25/0600Z 20.0N 31.0W 40 KT
72HR VT 26/0600Z 21.5N 32.5W 40 KT
96HR VT 27/0600Z 23.5N 35.0W 35 KT
120HR VT 28/0600Z 26.0N 38.0W 25 KT...POST-TROP/REMNT LOW

$$
FORECASTER KIMBERLAIN

[HURAKAN]

649
WTNT44 KNHC 231433
TCDAT4
TROPICAL DEPRESSION LISA DISCUSSION NUMBER 11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 AM AST THU SEP 23 2010

VISIBLE AND INFRARED SATELLITE IMAGERY INDICATES DEEP CONVECTION HAS
INCREASED AND BECOME A LITTLE BETTER ORGANIZED NEAR THE CENTER OF
LISA. A 23/0907Z SSMIS MICROWAVE OVERPASS INDICATED A WELL-DEFINED
CURVED BAND OF CONVECTION HAD FORMED AND WRAPPED BETTER THAN HALF
WAY AROUND THE NORTH AND WEST SIDE OF THE CENTER. DVORAK SATELLITE
INTENSITY ESTIMATES ARE T2.0/30 KT FROM TAFB...T1.5/25 FROM SAB.
UW-CIMSS ADT ESTIMATE REMAIN WELL ABOVE THE SUBJECTIVE INTENSITY
ESTIMATES AT T3.3/51 KT. THE INITIAL INTENSITY FOR THIS ADVISORY
WILL BE HELD AT 30 KT...WHICH COULD BE A LITTLE LOW GIVEN THE RECENT
UPWARD TREND NOTED IN THE VARIOUS SATELLITE DATA.

LISA HAS BEEN DRIFTING EASTWARD...BUT A SLOW NORTHWARD MOTION OF
360/02 IS EXPECTED TO BEGIN WITHIN THE NEXT 6-12 HOURS. WATER VAPOR
IMAGERY INDICATES THE ELONGATED MID- TO UPPER-LEVEL TROUGH THAT HAS
BEEN NUDGING LISA EASTWARD THE PAST FEW DAYS IS BEGINNING TO SHOW
SIGNS OF SLOWLY LIFTING OUT TO THE NORTHEAST. THIS SHOULD ALLOW THE
WEAKNESS IN THE SUBTROPICAL RIDGE TO THE NORTH OF THE CYCLONE TO
FILL IN AND BEGIN TO STEER LISA TO THE NORTH AND EVENTUALLY
NORTHWESTWARD. THE LATEST MODEL GUIDANCE IS CONSISTENT WITH THIS
DEVELOPING SCENARIO AND SHOWS LESS SPREAD THAN PREVIOUS MODEL RUNS.
THE NHC FORECAST TRACK HAS BEEN SHIFTED A LITTLE TO THE RIGHT OF
THE PREVIOUS OF ADVISORY TRACK...BUT REMAINS ALONG THE EXTREME LEFT
SIDE OF THE MODEL GUIDANCE ENVELOPE.

NOW THAT THE AFOREMENTIONED UPPER-LEVEL TROUGH AND ITS ASSOCIATED
SOUTHWESTERLY ARE MOVING AWAY FROM LISA...THE UPPER-LEVEL OUTFLOW
PATTERN HAS IMPROVED. HOWEVER...THE NEARBY PRESENCE OF DRY
MID-LEVEL AIR REMAINS PROBLEMATIC IN THE INTENSITY FORECAST
PROCESS. THE LOWEST SHEAR AND BEST MOISTURE PROFILES FOR
INTENSIFICATION TO OCCUR ARE EXPECTED TO AFFECT LISA DURING THE
NEXT 24-36 HOURS. AFTER THAT...DRIER MID-LEVEL AIR...COOLER
SSTS...AND INCREASING WESTERLY SHEAR AHEAD OF ANOTHER
MID-TROPOSPHERIC TROUGH ARE EXPECTED TO INDUCE A STEADY WEAKENING
TREND. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS
ADVISORY AND A BLEND OF NHC INTENSITY MODELS.


FORECAST POSITIONS AND MAX WINDS

INITIAL 23/1500Z 17.5N 28.9W 30 KT
12HR VT 24/0000Z 18.4N 29.2W 35 KT
24HR VT 24/1200Z 19.2N 29.6W 35 KT
36HR VT 25/0000Z 20.0N 30.3W 40 KT
48HR VT 25/1200Z 20.8N 31.0W 40 KT
72HR VT 26/1200Z 22.0N 32.2W 40 KT
96HR VT 27/1200Z 24.2N 35.0W 35 KT
120HR VT 28/1200Z 26.5N 37.5W 25 KT...POST-TROP/REMNT LOW

$$
FORECASTER STEWART

[cycloneye]

WTNT44 KNHC 232037
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 PM AST THU SEP 23 2010

MICROWAVE DATA A FEW HOURS AGO GAVE US A HINT THAT LISA WAS BECOMING
A LITTLE BETTER ORGANIZED...AND NOW CONVENTIONAL IMAGES SHOW MORE
SYMMETRIC CONVECTION AROUND THE CENTER WITH FAIR OUTFLOW.
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB INCREASED TO 2.5 ON
THE DVORAK SCALE. BASED ON THESE ESTIMATES...THE INITIAL INTENSITY
HAS BEEN ADJUSTED UPWARD TO 35 KNOTS AND LISA HAS ONCE AGAIN REACHED
TROPICAL STORM STATUS. THERE IS A SMALL OPPORTUNITY OF 24 TO 36
HOURS FOR LISA TO STRENGTHEN A LITTLE BEFORE THE SHEAR INCREASES. A
GRADUAL WEAKENING IS ANTICIPATED THEREAFTER.

LISA HAS BEEN MEANDERING OR NEARLY STATIONARY FOR THE PAST FEW HOURS
AND WILL LIKELY CONTINUE TO BE TRAPPED WITHIN VERY WEAK STEERING
CURRENTS FOR THE NEXT 12 HOUR OR SO. THE RIDGE TO THE EAST OF THE
CYCLONE IS EXPECTED TO BUILD AS A SHARP TROUGH TO THE NORTH MOVES
OUT OF THE AREA. THIS NEW STEERING PATTERN WILL FORCE LISA ON A
GENERAL NORTH TO NORTHWEST TRACK DURING THE NEXT FIVE DAYS. TRACK
MODEL OUTPUT RESEMBLES A FAN...WITH TRACKS VARYING FROM THE
WEST-NORTHWEST TO THE NORTHEAST. THE OFFICIAL FORECAST IS IN THE
MIDDLE OF THE LARGE GUIDANCE ENVELOPE AND IS HIGHLY UNCERTAIN.


FORECAST POSITIONS AND MAX WINDS

INITIAL 23/2100Z 17.5N 28.6W 35 KT
12HR VT 24/0600Z 17.5N 28.5W 40 KT
24HR VT 24/1800Z 19.0N 28.7W 45 KT
36HR VT 25/0600Z 20.5N 29.5W 35 KT
48HR VT 25/1800Z 22.0N 30.5W 35 KT
72HR VT 26/1800Z 24.0N 32.0W 30 KT
96HR VT 27/1800Z 26.0N 34.0W 25 KT
120HR VT 28/1800Z 28.5N 36.5W 20 KT...POST-TROP/REMNT LOW

$$
FORECASTER AVILA

[cycloneye]

WTNT44 KNHC 240253
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM AST THU SEP 23 2010

OVERALL...THE SATELLITE APPEARANCE OF LISA IS LESS ORGANIZED THAN
EARLIER WITH CENTRAL CONVECTION WEAKENING AND THUNDERSTORMS IN
OUTER BANDS ON THE INCREASE. DVORAK CI NUMBERS ARE UNCHANGED...
HOWEVER...SO THE INITIAL INTENSITY WILL REMAIN 35 KT. THE TROPICAL
CYCLONE HAS ABOUT 24 HOURS LEFT FOR SIGNIFICANT STRENGTHENING
BEFORE IT ENCOUNTERS A HOSTILE ENVIRONMENT OF SOUTHWESTERLY
SHEAR...COOLER WATERS...AND DRIER MID-LEVEL AIR. THE NHC INTENSITY
FORECAST IS REDUCED A BIT FROM THE PREVIOUS ONE...AND IS LOWER THAN
MOST OF THE GUIDANCE IN A COUPLE OF DAYS. REMNANT LOW STATUS IS
FORECAST IN 72 HOURS...AND IT WOULD NOT BE SURPRISING IF IT
HAPPENED SOONER.

A SERIES OF MICROWAVE IMAGES DURING THE PAST TWELVE HOURS INDICATE
THAT THE CENTER HAS BEEN MOVING SLOWLY EASTWARD. MORE RECENTLY...
CONVENTIONAL SATELLITE AND MICROWAVE DATA SUGGEST THAT A TURN
TOWARD THE LEFT HAS OCCURRED...WITH A MOTION OF ABOUT 020/4. THE
TRACK SHOULD CONTINUE TO SHIFT TOWARD THE NORTH AND NORTH-NORTHWEST
BY LATE TOMORROW AS RIDGING REDEVELOPS TO THE NORTHEAST OF LISA.
MOST OF THE RELIABLE MODELS ARE BECOMING BETTER CLUSTERED ON THIS
SOLUTION...THOUGH THE HWRF/GFDL ARE A LOT FARTHER NORTHEAST THAN
THE REST OF THE GUIDANCE. THE NHC FORECAST IS SHIFTED A BIT TO THE
RIGHT...BUT STILL REMAINS ON THE WEST SIDE OF THE GUIDANCE
ENVELOPE....GENERALLY BETWEEN THE ECMWF MODEL AND THE DYNAMICAL
MODEL CONSENSUS.


FORECAST POSITIONS AND MAX WINDS

INITIAL 24/0300Z 18.1N 28.1W 35 KT
12HR VT 24/1200Z 18.7N 28.1W 40 KT
24HR VT 25/0000Z 20.0N 28.6W 40 KT
36HR VT 25/1200Z 21.4N 29.3W 35 KT
48HR VT 26/0000Z 22.8N 30.0W 30 KT
72HR VT 27/0000Z 25.5N 32.0W 25 KT...POST-TROP/REMNT LOW
96HR VT 28/0000Z 27.5N 34.0W 20 KT...POST-TROP/REMNT LOW
120HR VT 29/0000Z 29.5N 36.5W 20 KT...POST-TROP/REMNT LOW

$$
FORECASTER BLAKE

[HURAKAN]

TROPICAL STORM LISA DISCUSSION NUMBER 14
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 AM AST FRI SEP 24 2010

INFRARED SATELLITE IMAGES SHOW THAT DEEP CONVECTION HAS RE-DEVELOPED
AROUND THE LOW-LEVEL CENTER OF LISA IN RECENT HOURS AS CONVECTION
IN A BAND WELL NORTHEAST OF THE CENTER HAS GENERALLY BEEN
DECREASING. DESPITE THE INCREASE IN CENTRAL CONVECTION...THE
OVERALL CLOUD PATTERN OF THE CYCLONE HAS NOT CHANGED MUCH IN
ORGANIZATION. DVORAK CI NUMBERS REMAIN UNCHANGED AT 2.0 AND 2.5
FROM SAB AND TAFB...RESPECTIVELY...AND ARE THE BASIS FOR KEEPING
THE INITIAL INTENSITY AT 35 KT. THE POSSIBILITY OF LISA INTENSIFYING
IS DECREASING. IN LESS THAN 24 HOURS...LISA IS EXPECTED TO REACH AN
ENVIRONMENT OF INCREASING SOUTHWESTERLY VERTICAL WIND SHEAR...
COOLER WATERS...AND HIGHER STABILITY. THESE FACTORS SHOULD PROMOTE
A STEADY WEAKENING...PERHAPS MORE RAPID THAN CURRENTLY FORECAST.
THE NHC INTENSITY FORECAST IS ABOUT THE SAME AS THE PREVIOUS ONE
BUT REMAINS A BIT LOWER THAN MOST OF THE STATISTICAL-DYNAMICAL
GUIDANCE.

AN 0349 UTC AMSR-E MICROWAVE OVERPASS WAS HELPFUL IN DETERMINING THE
CENTER OF LISA. THE CYCLONE APPEARS TO BE DRIFTING NORTHEASTWARD...
AND THE INITIAL MOTION ESTIMATE IS 035/04. GLOBAL MODELS SHOW LISA
MOVING GENERALLY NORTHWARD WITH SOME INCREASE IN FORWARD SPEED
DURING THE NEXT COUPLE OF DAYS...STEERED AROUND THE WESTERN
PERIPHERY OF A LOW- TO MID-LEVEL RIDGE OVER NORTHWEST AFRICA. AFTER
THAT...A WEAKER LISA OR ITS REMNANTS SHOULD MOVE NORTH-
NORTHWESTWARD IN THE LOW-LEVEL FLOW AND EVENTUALLY DISSIPATE. THE
NEW NHC TRACK FORECAST IS ADJUSTED A BIT TO THE RIGHT BUT NOT AS
FAR EAST AS THE GFDL/HWRF/UKMET WHICH GENERALLY HAVE STRONGER AND
LIKELY UNREALISTIC REPRESENTATIONS OF LISA...ESPECIALLY BEYOND 48
HOURS. THE NHC TRACK IS LEFT OF THE DYNAMICAL MODEL CONSENSUS AND
ROUGHLY IN THE MIDDLE OF THE GUIDANCE ENVELOPE.



FORECAST POSITIONS AND MAX WINDS

INITIAL 24/0900Z 18.4N 27.7W 35 KT
12HR VT 24/1800Z 19.2N 27.9W 40 KT
24HR VT 25/0600Z 20.6N 28.3W 35 KT
36HR VT 25/1800Z 22.1N 28.8W 30 KT
48HR VT 26/0600Z 23.6N 29.2W 30 KT
72HR VT 27/0600Z 26.0N 30.5W 25 KT...POST-TROP/REMNT LOW
96HR VT 28/0600Z 27.5N 32.0W 20 KT...POST-TROP/REMNT LOW
120HR VT 29/0600Z...DISSIPATED

$$
FORECASTER KIMBERLAIN

[cycloneye]

WTNT44 KNHC 242045
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 16
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 PM AST FRI SEP 24 2010

CONVENTIONAL AND MICROWAVE SATELLITE IMAGERY INDICATES LISA HAS
CONTINUED TO BECOME BETTER ORGANIZED AND HAS STRENGTHENED. A RECENT
TRMM OVERPASS REVEALED A CLOSED LOW-LEVEL EYE WITH A DIAMETER OF
ABOUT 8-10 NMI...AND VISIBLE AND INFRARED IMAGERY HAVE BEEN HINTING
THAT AN EYE HAS ALSO BEEN TRYING TO FORM. THE INITIAL INTENSITY OF
50 KT IS BASED ON A BLEND OF SATELLITE ESTIMATES OF T3.0/45 KT FROM
BOTH TAFB AND SAB...TAFB AODT ESTIMATES OF T3.4/53 KT...AND
UW-CIMSS 3-HR AVERAGE ADT ESTIMATES OF T3.4/53 KT. GIVEN THE VERY
SMALL SIZE OF THE INNER-CORE CIRCULATION...WHICH RESTRICTS THE
VARIOUS SATELLITE INTENSITY TECHNIQUES...IT IS POSSIBLE THAT LISA
COULD BE STRONGER THAN INDICATED IN THIS ADVISORY.

THE INITIAL MOTION ESTIMATE IS 360/07. FOR THE NEXT 24-36 HOURS...
LISA IS FORECAST TO MOVE NORTHWARD AROUND THE WESTERN PERIPHERY OF
THE LARGE SAHARAN SUBTROPICAL RIDGE LOCATED TO THE EAST OF THE
CYCLONE. BY 48 HOURS...LISA IS EXPECTED TO MOVE INTO AN ENVIRONMENT
OF STRONG SOUTHWESTERLY SHEAR FORECAST TO DEVELOP AHEAD OF A
SHORTWAVE TROUGH CURRENTLY DIGGING SOUTHEASTWARD OVER THE CENTRAL
ATLANTIC. THE EXPECTED RESULT IS THAT THE LOW-LEVEL AND UPPER-LEVEL
CIRCULATIONS WILL DECOUPLE IN 72-96 HOURS...WITH THE LOW-LEVEL
CIRCULATION MOVING NORTH-NORTHWESTWARD OR EVEN NORTHWESTWARD AS A
REMNANT LOW PRESSURE SYSTEM THAT WILL BE STEERED BY THE LARGE
SURFACE BERMUDA HIGH LOCATED OVER THE CENTRAL ATLANTIC. IN
CONTRAST...THE GFDL AND HWRF MODELS MOVE LISA NORTHEASTWARD AFTER
72 HOURS AS A SIGNIFICANT TROPICAL CYCLONE. THOSE SCENARIOS ARE
BEING DISCOUNTED AT THIS TIME DUE TO THEIR KNOWN BIAS IN RESISTING
STRONG VERTICAL SHEAR CONDITIONS. THE OFFICIAL FORECAST TRACK IS A
LITTLE TO THE RIGHT OF THE PREVIOUS ADVISORY...AND IS CLOSE TO THE
NHC CONSENSUS MODEL...TVCN.

SATELLITE IMAGERY SHOWS MODERATE CONVECTION OCCURRING AT LEAST 200
NMI TO THE NORTH OF LISA. THIS INDICATES THAT THERE IS AVAILABLE
INSTABILITY FOR THE CYCLONE TO TAP IN TO DESPITE THE SUB-26C SSTS
THAT LIE AHEAD OF THE SYSTEM. AS A RESULT...SOME ADDITIONAL
STRENGTHENING IS EXPECTED DURING THE NEXT 12-24 HOURS...AND IT IS
POSSIBLE THAT LISA COULD BECOME A HURRICANE. HOWEVER...BY 36 HOURS
LISA IS FORECAST TO ENCOUNTER STRONG SHEAR OF MORE THAN 30 KT...
WHICH SHOULD INDUCE STEADY WEAKENING. LISA IS FORECAST TO DEGENERATE
INTO A REMNANT LOW PRESSURE SYSTEM BY 96 HOURS AND DISSIPATE BY 120
HOURS. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO A BLEND OF THE
SHIPS AND LGEM INTENSITY MODELS AT ALL TIMES.


FORECAST POSITIONS AND MAX WINDS

INITIAL 24/2100Z 20.0N 27.8W 50 KT
12HR VT 25/0600Z 21.0N 28.0W 55 KT
24HR VT 25/1800Z 22.5N 28.3W 50 KT
36HR VT 26/0600Z 24.1N 28.7W 45 KT
48HR VT 26/1800Z 25.3N 29.1W 35 KT
72HR VT 27/1800Z 27.3N 29.9W 30 KT
96HR VT 28/1800Z 29.0N 30.5W 25 KT...POST-TROP/REMNT LOW
120HR VT 29/1800Z...DISSIPATED

$$
FORECASTER STEWART

[cycloneye]

242257
TCDAT4
HURRICANE LISA SPECIAL DISCUSSION NUMBER 17
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
700 PM AST FRI SEP 24 2010

LISA HAS DEVELOPED A SMALL BUT WELL-ORGANIZED EYE SURROUNDED BY A
RING OF CLOUD TOPS COLDER THAN -70C AS SEEN IN GEOSTATIONARY
IMAGERY DURING THE PAST COUPLE OF HOURS. THIS EYE IS ALSO
CONFIRMED BY A RECENT SSMI/S MICROWAVE PASS. SPECIAL DVORAK
CLASSIFICATIONS FROM AROUND 2200 UTC BY TAFB AND SAB WERE BOTH
4.0...65 KT...SO THE INITIAL INTENSITY WILL BE RAISED TO THAT
VALUE. LISA IS STILL EXPECTED TO BEGIN TO WEAKEN TOMORROW AS IT
ENCOUNTERS STRONGER SHEAR AND COOLER WATERS. THE NEW INTENSITY
FORECAST IS NEAR...BUT A LITTLE HIGHER THAN...THE DYNAMICAL MODEL
CONSENSUS DURING THE FIRST 48 HOURS.

NO CHANGES HAVE BEEN MADE TO THE TRACK FORECAST AT THIS TIME.

FORECAST POSITIONS AND MAX WINDS

INITIAL 24/2300Z 20.2N 27.8W 65 KT
12HR VT 25/0600Z 21.0N 28.0W 70 KT
24HR VT 25/1800Z 22.5N 28.3W 65 KT
36HR VT 26/0600Z 24.1N 28.7W 55 KT
48HR VT 26/1800Z 25.3N 29.1W 40 KT
72HR VT 27/1800Z 27.3N 29.9W 30 KT
96HR VT 28/1800Z 29.0N 30.5W 25 KT...POST-TROP/REMNT LOW
120HR VT 29/1800Z...DISSIPATED

$$
FORECASTER BLAKE

[cycloneye]

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
HURRICANE LISA DISCUSSION NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM AST FRI SEP 24 2010

RECENT SATELLITE IMAGES SHOW THAT THE EYE OF LISA HAS BECOME
OBSCURED BY CIRRUS CLOUDS. HOWEVER...THE LATEST MICROWAVE PASS FROM
AROUND 2300 UTC STILL SHOWED THAT AN EYE WAS PRESENT. SATELLITE
ESTIMATES FROM TAFB AND SAB REMAIN 65 KT...THOUGH THE DATA-T VALUES
WERE HIGHER...AND THE ADT FROM UW-CIMSS WAS 72 KT. THE INITIAL
WINDS ARE SLIGHTLY INCREASED TO 70 KT AS A BLEND OF THESE DATA.
LISA BASICALLY HAS THE OVERNIGHT HOURS LEFT FOR ANY STRENGTHENING
UNTIL SOUTHWESTERLY SHEAR IS FORECAST BY ALL MODELS TO INCREASE. AS
THE CYCLONE MOVES FARTHER NORTH...IT SHOULD ALSO INGEST DRIER AIR
AND BE AFFECTED BY COOLER WATER TEMPERATURES. THUS STEADY WEAKENING
IS FORECAST TO BEGIN TOMORROW...AND THE NHC FORECAST IS CLOSE TO
THE SHIPS MODEL. SINCE LISA IS MUCH STRONGER THAN ANTICIPATED...
REMNANT LOW STATUS IS NOT FORECAST UNTIL DAY 4...THOUGH IT WOULD NOT
BE SURPRISING FOR IT TO HAPPEN SOONER DUE TO LISA REMAINING OVER
SUB-26C WATERS.

THE INITIAL MOTION CONTINUES TO BE 360/7. THERE HAS BEEN A SUBTLE
SHIFT IN THE SYNOPTIC PATTERN FORECAST BY MOST OF THE MODELS DURING
THE PAST SEVERAL CYCLES. A MID- TO UPPER-LEVEL TROUGH ALONG 35W IS
ADVANCING CLOSER TO THE TROPICAL CYCLONE THAN PREVIOUSLY EXPECTED.
CONSEQUENTLY...LESS RIDGING IS FORECAST TO BUILD TO THE NORTHEAST
OF THE CYCLONE...WHICH WOULD ALLOW A MORE NORTHWARD TRACK RATHER
THAN NORTHWESTWARD. AS LONG AS LISA REMAINS A VERTICALLY STACKED
SYSTEM...A GENERAL MOTION TOWARD THE NORTH IS LIKELY...SIMILAR TO
THE GFS AND ITS DEPENDENT MODEL SUITE. A NORTHWESTWARD TURN IS
POSSIBLE BY THE END OF THE FORECAST PERIOD...BUT THE SYSTEM WILL
EITHER BE A REMNANT LOW OR DISSIPATED BY THEN. THE NHC FORECAST IS
SHIFTED TO THE RIGHT...AGAIN...BUT REMAINS TO THE WEST OF THE
DYNAMICAL MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 25/0300Z 20.7N 27.9W 70 KT
12HR VT 25/1200Z 21.9N 28.1W 75 KT
24HR VT 26/0000Z 23.7N 28.3W 65 KT
36HR VT 26/1200Z 25.0N 28.5W 55 KT
48HR VT 27/0000Z 26.4N 28.8W 45 KT
72HR VT 28/0000Z 28.5N 29.2W 30 KT
96HR VT 29/0000Z 30.5N 29.5W 25 KT...POST-TROP/REMNT LOW
120HR VT 30/0000Z...DISSIPATED

$$
FORECASTER BLAKE

NNNN

[cycloneye]

WTNT44 KNHC 251443
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 AM AST SAT SEP 25 2010

ALTHOUGH OUTER BANDING FEATURES IN THE NORTHERN AND WESTERN
QUADRANTS HAVE ACTUALLY IMPROVED SINCE THE LAST ADVISORY...
SATELLITE IMAGERY INDICATES THE CENTRAL DEEP CONVECTION HAS ERODED
SOME DUE TO MODERATE WESTERLY SHEAR IMPINGING ON LISA. THE INITIAL
INTENSITY OF 60 KT IS BASED ON A BLEND OF SATELLITE INTENSITY
ESTIMATES T4.5/77 KT FROM TAFB... T2.4/35 KT FROM SAB...AND AN ADT
VALUE OF T3.8/61 KT FROM UW-CIMSS....AND THE CYCLONE HAS BEEN
DOWNGRADED TO TROPICAL STORM STATUS AGAIN.

LISA IS ON THE PREVIOUS FORECAST TRACK AND THE INITIAL MOTION
ESTIMATE IS NOW 350/10. THROUGHOUT THE FORECAST PERIOD...LISA IS
EXPECTED TO MOVE NORTH TO NORTH-NORTHWESTWARD AROUND THE WESTERN
PERIPHERY OF THE BROAD SUBTROPICAL RIDGE SITUATED OVER NORTHWESTERN
AFRICA. ALL OF THE GLOBAL AND REGIONAL MODELS ARE IN MUCH BETTER
AGREEMENT ON THIS SCENARIO THAN IN PREVIOUS MODEL RUNS...ASSUMING
THAT LISA MAINTAINS VERTICAL COHERENCE THROUGH AT LEAST 72 HOURS.
THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS ADVISORY AND
IS CLOSE TO THE CONSENSUS MODEL...TVCN.

WESTERLY TO SOUTHWESTERLY VERTICAL SHEAR IS FORECAST TO INCREASE TO
ABOVE 25 KT BY 24 HOURS AND CONTINUE INCREASE TO NEAR 35 KT BY
36-48 HOURS. THIS UNFAVORABLE UPPER-LEVEL FLOW PATTERN SHOULD
CONTINUE THE CURRENT WEAKENING TREND. ALTHOUGH LISA IS PRESENTLY
LOCATED OVER RELATIVELY COOL SSTS OF 25.5C...THE CYCLONE IS NOT
FORECAST TO MOVE OVER WATER ANY COOLER THAN THOSE CURRENT OCEAN
TEMPERATURES. HOWEVER...THE GFS-BASED SHIPS MODEL INDICATES THAT
UPPER-LEVEL TEMPERATURES ARE FORECAST TO COOL BY AT LEAST 3 DEGREES
CELSIUS...WHICH WOULD RESULT IN GREATER INSTABILITY AHEAD OF LISA
THAN WHAT THE CYCLONE IS CURRENTLY INGESTING. THE RESULT IS THAT
DEEP CONVECTION COULD PERSIST NEAR THE CENTER...ALBEIT SHEARED TO
THE EAST...AND PREVENT LISA FROM BECOMING A NON-CONVECTIVE REMNANT
LOW PRESSURE SYSTEM AS EARLY AS INDICATED BY THE OFFICIAL FORECAST.


FORECAST POSITIONS AND MAX WINDS

INITIAL 25/1500Z 22.7N 28.2W 60 KT
12HR VT 26/0000Z 23.9N 28.4W 50 KT
24HR VT 26/1200Z 25.3N 28.6W 45 KT
36HR VT 27/0000Z 26.6N 28.8W 40 KT
48HR VT 27/1200Z 27.9N 29.1W 35 KT
72HR VT 28/1200Z 30.1N 29.6W 30 KT...POST-TROP/REMNT LOW
96HR VT 29/1200Z 32.0N 30.0W 25 KT...POST-TROP/REMNT LOW
120HR VT 30/1200Z...DISSIPATED

$$
FORECASTER STEWART

[cycloneye]

TROPICAL STORM LISA DISCUSSION NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
500 PM AST SAT SEP 25 2010

CONVENTIONAL AND MICROWAVE SATELLITE IMAGERY INDICATE WESTERLY SHEAR
IS TAKING ITS TOLL ON LISA WITH ITS UPPER-LEVEL ANTICYCLONE NOW
DISPLACED MORE THAN 100 NMI TO THE EAST OF THE LOW-LEVEL CENTER. AS
A RESULT...SATELLITE INTENSITY ESTIMATES HAVE BEEN RAPIDLY
DECREASING DURING THE PAST 6 HOURS. THE INITIAL INTENSITY OF 45 KT
IS BASED ON A BLEND OF SATELLITE INTENSITY ESTIMATES T3.5/55 KT
FROM TAFB...T1.5/25 KT FROM SAB...AND AN ADT VALUE OF T3.0/45 KT
FROM UW-CIMSS.

THE INITIAL MOTION ESTIMATE IS 350/10. LISA REMAINS ON TRACK AND THE
CYCLONE IS EXPECTED TO TURN TOWARD THE NORTH-NORTHWEST DURING THE
NEXT 12 HOURS OR SO...AND CONTINUE THAT MOTION FOR THE REMAINDER OF
THE FORECAST PERIOD. THE NHC MODEL GUIDANCE IS MUCH MORE CONVERGENT
NOW...AND THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS
ADVISORY TRACK AND IS A LITTLE TO THE RIGHT OF THE MODEL CONSENSUS.

WESTERLY TO SOUTHWESTERLY VERTICAL SHEAR IS FORECAST TO INCREASE TO
MORE THAN 30 KT BY 24 HOURS...WHICH COULD HASTEN THE ONGOING
WEAKENING TREND. THE GFS-BASED SHIPS MODEL INDICATES DISSIPATION BY
48 HOURS...BUT THE OFFICIAL FORECAST DELAYS DISSIPATION DUE TO
INTERMITTENT BURSTS OF DEEP CONVECTION POSSIBLY KEEPING THE
CIRCULATION ALIVE A LITTLE BIT LONGER...WHICH IS SIMILAR TO THE
LGEM...HWRF...AND GFDL SOLUTIONS. THE OFFICIAL INTENSITY FORECAST
IS SIMILAR TO THE PREVIOUS ADVISORY AND IS A BLEND OF THE NHC
OBJECTIVE INTENSITY GUIDANCE.


FORECAST POSITIONS AND MAX WINDS

INITIAL 25/2100Z 23.7N 28.4W 45 KT
12HR VT 26/0600Z 24.7N 28.6W 40 KT
24HR VT 26/1800Z 26.1N 28.8W 35 KT
36HR VT 27/0600Z 27.4N 29.0W 30 KT
48HR VT 27/1800Z 28.6N 29.3W 30 KT
72HR VT 28/1800Z 30.7N 30.0W 25 KT...POST-TROP/REMNT LOW
96HR VT 29/1800Z 32.5N 30.5W 25 KT...POST-TROP/REMNT LOW
120HR VT 30/1800Z...DISSIPATED

$$
FORECASTER STEWART

[cycloneye]

000
WTNT44 KNHC 260234
TCDAT4
TROPICAL STORM LISA DISCUSSION NUMBER 22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142010
1100 PM AST SAT SEP 25 2010

MICROWAVE IMAGES FROM THIS EVENING INDICATE THAT LISA HAS BEEN
MOVING MORE TOWARD THE NORTH-NORTHWEST...WITH THE CENTER BECOMING
EXPOSED TO THE SOUTHWEST OF VERY LIMITED DEEP CONVECTION. DVORAK
CLASSIFICATIONS ARE DECREASING AS FAST AS THE RULES ALLOW...AND THE
INITIAL WIND SPEED IS LOWERED TO 40 KT. COOL WATERS...DRY AIR...AND
STRONG SOUTHWESTERLY SHEAR SHOULD FINISH OFF LISA BY MONDAY UNLESS
THE CYCLONE PULLS ANOTHER SURPRISE. THE GUIDANCE IS IN GOOD
AGREEMENT ON THE WEAKENING SCENARIO...AND THE OFFICIAL FORECAST IS
BASICALLY AN UPDATE OF THE PREVIOUS ONE.

BASED ON SSMI/S IMAGES FROM EARLIER THE LOW-LEVEL CENTER HAS BEEN
RELOCATED FARTHER WEST...AND IS MOVING AT ABOUT 340/8. A NORTH-
NORTHWESTWARD MOTION IS EXPECTED UNTIL DISSIPATION IN A DAY OR TWO
AS THE CYCLONE MOVES BETWEEN A TROUGH OVER THE EASTERN ATLANTIC
OCEAN AND RIDGE NEAR NORTHWESTERN AFRICA. SOME MODEL GUIDANCE...
SUCH AS THE HWRF/GFDL...SHOW THE CYCLONE TAKING A TRACK TOWARD THE
NORTH OR NORTH-NORTHEAST...BUT THESE MODELS ALSO HAVE A MUCH MORE
VERTICALLY COHERENT CYCLONE. SINCE THIS STRUCTURE IS UNLIKELY TO
OCCUR...THE NHC FORECAST WILL REMAIN ON THE LEFT SIDE OF THE
GUIDANCE. THE NEW FORECAST HAS BEEN SHIFTED TO THE WEST...BUT THAT
IS MOSTLY DUE TO THE CENTER RELOCATION. THE REMNANT LOW SHOULD MOVE
VERY SLOWLY BY THE END OF THE PERIOD AS SURFACE HIGH PRESSURE
BUILDS NEAR THE AZORES.


FORECAST POSITIONS AND MAX WINDS

INITIAL 26/0300Z 24.3N 29.0W 40 KT
12HR VT 26/1200Z 25.3N 29.3W 35 KT
24HR VT 27/0000Z 26.5N 29.6W 30 KT
36HR VT 27/1200Z 27.8N 30.0W 25 KT...POST-TROP/REMNT LOW
48HR VT 28/0000Z 29.2N 30.6W 25 KT...POST-TROP/REMNT LOW
72HR VT 29/0000Z 31.0N 31.0W 25 KT...POST-TROP/REMNT LOW
96HR VT 30/0000Z 32.0N 31.0W 20 KT...POST-TROP/REMNT LOW
120HR VT 01/0000Z...DISSIPATED

$$
FORECASTER BLAKE